1. Field of the Invention
Often in conventional flush tank toilets less than a full tank of water will satisfactorily flush the toilet. Accordingly, one way to conserve water, which is so wastefully flushed through toilets, is to provide a selective flushing system which utilizes a full flush cycle for solids and partial flush for liquids.
2. Description of Prior Art
Dual flush systems to achieve the above purpose follow four basic designs:
A. They utilize multiple outlet ports, set at two or more elevations in the tank. These ports can be selectively opened for the desired flush. PA1 B. The large float which controls the water inlet valve, is utilized to close the outlet valve selectively. PA1 C. The buoyancy of a hollow outlet valve is selectively controlled. PA1 D. An independent float is selectively controlled so as to close the outlet valve at a desired elevation of the water in the tank.
Most of these mechanisms in the prior art have proved unreliable in daily operations or very costly to install.